[UNRESOLVED NEED MORE INFO] Waiting list

The doctors treat the latest patient arrived so I have notifications that tells me that my patient is gonna leave

Hi, thanks for the message!

The order in which the patients get called is normally the same as the order they've arrived to the waiting room (plus some patients get assigned a higher priority at the reception).
But when the patients wait for a long time and go fill their needs, somebody can get called in instead (and I think they end up back at the end of the queue). Does this seem to match what you're experiencing? Btw could you also check what workload levels you can see at the end of the shift in management mode for your doctor's offices?